Rokuji-Raisan is a Pure Land Sect Buddhist memorial service. It is a service carried out according to the six times of the day consisting of sutra chanting, nenbutsu recitation and prayer based on the 'Ojoraisange' of Chinese monk Shandao. In the Kamakura period, Pure Land Sect founder Honen put tunes to Buddhist worship to create one of the nenbutsu-zanmai (mental absorption in the nenbutsu) practices.
It was characterized by the beautiful melody of the Tendai Shomyo (Buddhist liturgical chant) with a high-pitched tone used in the second half to increase the sense of solemnity. This practice became the reason for the religious persecution called Jogen no Honan (Kenei no Honan). Today it is widely used in the services of the Pure Land Sect, Ji Sect and Jodo Shinshu (the True Pure Land Sect of Buddhism). Shinran's Shoshin Nenbutsuge (Buddhist verses) were created with inspiration from Rokuji-Raisan.
The rokuji are generally considered to consist of the following six parts.
Nichimotsu: Saru-tori no koku (from around 4 p.m. to around 6 p.m.)
Shoya: Inu-I no koku (from around 8 p.m. to around 10 p.m.)
Chuya or Hanya: Ne-ushi no koku (from around midnight to around 2 a.m.)
Goya: Tora-u no koku (from around 4 a.m. to around 6 a.m.)
Jinjo/Shincho: Tatsu-mi no koku (from around 8 a.m. to around 10 a.m.)
Nicchu: Uma-hitsuji no koku (from around noon to around 2 p.m.)
The word 'shirokujichu' (meaning all the time) is derived from the four times of the day known as 'shiji' (early morning, noon, late afternoon and dusk) in combination with the six times of the day known as 'rokuji.'
The practice of conducting Buddhist ceremonies according to the rokuji times of the day is not limited to the Pure Land Sect and can also be seen in the Shunie ceremony of Todai-ji Temple.